Peripherals

BNO055

• Adafruit BNO055 Absolute Orientation Sensor

HT16K33 LED Backpack

• 0.54" 14-segment LED HT16K33 Backpack
• Default I2C address of the display is 0x70
• documentation
• Adafruit_CircuitPython_HT16K33 How-To

import board
import busio as io
i2c = io.I2C( board.SCL, board.SDA )
import adafruit_ht16k33.segments
display = adafruit_ht16k33.segments.Seg14x4( i2c )#, address=0x74)
display.fill(0)
display.print('CPY!')
display.show()

Velleman VMA412 RGB TFT display

• VMA42 website with downloads
• 2.8" touch screen, 240x320 RGB, ILI9341 display driver
• CircuitPython display driver for ILI9341
• CircuitPython touch screen library
• Most examples use four-wire SPI bus, plus calls into displayio objects/methods

74HC595

• Texas Instruments SN74HC595N 8-Bit Shift Registers With 3-State Output Registers
• Cost $4.84/4
• 8-bit serial-in
• parallel-out shift register that feeds an 8-bit D-type storage register
• The storage register has parallel 3-state outputs
• Separate clocks are provided for both the shift and storage register
• The shift register has a direct overriding clear (SRCLR) input, serial (SER) input, and serial outputs for cascading
• When the output-enable (OE) input is high, the outputs are in the high-impedance state
• Both the shift register clock (SRCLK) and storage register clock (RCLK) are positive-edge triggered
• If both clocks are connected together, the shift register always is one clock pulse ahead of the storage register.

ULN2803

• ULN2803APG DIP-18 ULN2803 is high-voltage, high-current Darlington drivers comprised of eight NPN Darlington pairs
• Output current (single output) 500mA MAX

TLC5940NT

• TLC5940 16-Channel LED Driver With DOT Correction and Grayscale PWM Control
• data sheet

Transitors

• Used as amplifiers or switches
• form factors
  • TO 92
  • 2N3904
  • TO220
• Heat sinks are electrically to heat sink (center lead)

BJT

• Bipolar Junction Transistor
• BJTs are current driven
• NPN most common
  • Apply small current to base
  • Allows high current to flow through collector emitter

Amplification at $V_{CE}=5V$ & 10x White LEDs

• BC337 with 10x Yellow at 12ma I_BE has 1.50V

Type	$V_{BEmin}$	$I_{CEmin}$	$V_{BE}{\textrm {when}}I_{BE}=12mA$	$I_{CE}{\textrm {when}}I_{BE}=12mA$	$HF{\textrm {when}}I_{BE}=12mA$
2N2222A	0.32V	2.37mA	1.88V	64mA	5.33x
BC337	0.32V	0.01mA	1.08V	130mA	10.8x
S8050	0V	0.17mA	1.10V	130mA	10.8x

• BC337 - collector base emitter left to right
• 2N2222 NPN paired with 2N2907 PNP. General purpose low power bipolar transistors.

MOSFET

• N-channel and P-channel
• 3 leads: gate, drain, source goes left to right while looking at the front. drain on top for heat dissipation
• N-channel
  • Low voltage applied to the gate
  • Drops resistance between drain and source down to almost zero

IRLB8721

• IRLB8721PBF 30V 62A N-Channel Power MOSFET TO-220
• L in IRL means logic, i.e. able to be driven by 3.3V
• data sheet

BS170_D26Z

• FAIRCHILD SEMICONDUCTOR BS170_D26Z N CHANNEL MOSFET, 60V, 500mA, TO-92
• $6.50 for 10
• BS170-1118810 data sheet
• Drain, Gate, Source, left to right facing the front
• 500 mA
• Gate threshold voltage
  • 0.8V min
  • 2.1V typical
  • 3 max
• turn on turn off time = 10 nanoseconds

LEDs

The ones I bought

• Soldering @ 260 deg C
• Red, Yellow and Green have ~2V Forward Voltage, at 20mA current
• Blue and White have ~3.3V Forward Voltage, at 20mA current
• They all operate @ 5V